This adds new options for user to choose how the terrain should be rendered:
- shading disabled - color of terrain is determined only from map texture
- shading enabled - color of terrain is determined using Phong's shading model,
taking into account map texture, terrain normal vector, scene light(s) and
terrain material's ambient+specular colors and shininess
(configuration of lights is not there yet - now we always have a single point
light with white color at the middle of the scene at 1km above the zero elevation)
Even preventing their output isn't enough here. There's just
SO many debug msgs throughout this class, that creating and
parsing the debug messages strings (which is done even if
the message level is higher than is output) is enough
to grind the import to a halt on debug enabled builds.
render exterior ring or interior rings
This option is shown whenever a simple line symbol or
marker line symbol is used as part of a fill symbol for
rendering polygons.
The default behavior is to render both interior and exterior
rings, but this new setting allows users to set the symbol
layer to render only for the exterior ring OR only
for interior rings.
This allows for symbolisation which wasn't directly possible
before, such as a marker line with markers for interior
rings angled toward the interior of the polygon.
Sponsored by the German QGIS User Group
Fixes#12652
This new option, available under the "Advanced" button for fill symbols,
allows forcing rendered polygons to follow the standard "right hand
rule" for ring orientation (where exterior ring is clockwise, and
interior rings are all counter-clockwise).
The orientation fix is applied while rendering only, and the original
feature geometry is unchanged.
This allows for creation of fill symbols with consistent appearance,
regardless of the dataset being rendered and the ring orientation
of individual features.
Refs #12652
This algorithm forces polygon geometries to respect the Right-Hand-Rule,
in which the area that is bounded by a polygon is to the right of the
boundary. In particular, the exterior ring is oriented in a clockwise
direction and the interior rings in a counter-clockwise direction.
Forces polygons to follow the right hand rule, in which the area that
is bounded by a polygon is to the right of the boundary. In particular,
the exterior ring is oriented in a clockwise direction and the
interior rings in a counter-clockwise direction.